Tuesday, March 31, 2015

Japanese Armour

In the Japanese language the word
for battle, sen, has been combined with the word for wagon, sha, to
form sensha, a tank. Japanese interest in armoured fighting vehicles can
be traced back to the 1920s when the British firm of Vickers persuaded the
Japanese War Ministry to buy one of the Medium C tanks which Vickers salesmen
were endeavouring to sell to a number of foreign powers. In fact the Japanese
had already embarked on the building of a heavy tank, but when their designers
ran into trouble from lack of experience they decided to adapt foreign designs
to their requirements.

Thus in 1929 when Japan started producing her own tanks
they were based on early models of the French Renault M1917, the Vickers Medium
C, and the Carden-Loyd light tank Mark VI. For the most part the Japanese
models closely followed the design of the originals. The Type 89A which
appeared in 1929, for example, bore a strong resemblance to the original Mark C
prototype which Vickers had supplied to Japan in response to their order for a
Medium C three years previously. However, the Type 89A had thicker armour, only
two machine guns instead of four, and a crew of four instead or the five needed
in the Mark C. The Japanese tank also had a stronger suspension, but this and
the additional weight of the armour resulted in a slower speed. In effect the
Japanese had converted a fast light tank into an infantry support vehicle. The
decision to do so was to be reflected in subsequent Japanese armoured policy up
to 1945. Tanks were generally regarded as subordinate to the traditional arms,
and not as an arm of decision in their own right.

In 1932 the experimental Type 89A
was followed by the Type 92, a so-called 'heavy' tank (of 26 tons) whose 34
bogie wheels gave it the appearance of a giant man-made centipede. The Type 92
did not prove successful and the Japanese turned to the design of lighter
armoured fighting vehicles more in keeping with their maritime strategy aimed
at weaker opponents.

The first Japanese tankette came
into service in 1932, and was clearly a development of the Garden Loyd series
of weapon carriers. Like the thin-skinned light tank T95 which appeared in
quantity three years later, the tankette was used with success against the
Chinese in the Sino-Japanese war. The Chinese had no effective equipment with
which to counter the Japanese armour and the fact that they frequently conceded
a battle when Japanese tankettes and Type 95s appeared undoubtedly distorted
Japanese views of armoured fighting vehicles. While the development of tanks
and tank tactics was accelerating in Europe, Japanese technology made little
advance, probably because the theatres in which they expected to fight were not
suited to uninhibited tank battles. Shortly before the war in Europe, however,
Japan did introduce a new tank which owed much to her own designers. This was
the medium Type 97, known also as the Chi-Ha, which went into service in
1942. Developed from the Type 95, the Chi-Ha was eventually developed to
carry a variety of armaments, including in one version a 150mm gun, and in
another, a 300mm mortar.

By European standards the armour of
the Japanese tanks was thin, but the main armament was comparable with
equivalent British and American tanks so far as calibre and weight of
projectile was concerned.

Tanks were named after the
manufacturer, and — like their other weapons and military stores — numbered by
the Japanese calendar year, dates being taken from 660 BC (which was their year
00). Thus the European equivalent of a year date is found by subtracting 660.

Turrets:
were all round or oval.

Armament: In some models a machine gun was mounted in the back plate
of the turret. Special machine gun compartments were often built out of the
superstructure. Machine guns were seldom, if ever, mounted coaxially with the
main armament.

Armour: The most heavily armoured Japanese tank of World War II was
the obsolescent M2595, 27 ton heavy tank, with 35mm (1.38in) armour on the
front.

This was inadequate in a tank of
this weight. The Japanese generally used rolled armour with welded and riveted
joints, both types of joint being commonly found in the same tank. The use of
curved plates was a common feature.

Suspension: In the tankette, and the latest light and medium tanks, the
Japanese used modified Carden-Loyd suspension in which the weight of the tank
was supported by horizontal compression springs arranged inside tubular
protective casings on each side of the hull between the bogie wheels and return
rollers.

Speed: Maximum speeds were not high, but the power-weight ratios
(25 for the light tank) resulted in good cross-country speeds.

Lightness: The Japanese have emphasised lightness, and track pressures
were low, giving an important advantage when travelling over soft ground.

Insulation: Woven asbestos heat insulation was placed inside the hull
and turret of the tankette and light tank.

Pages

About Me

Mitch Williamson is a technical writer with an
interest in military and naval affairs. He has published articles in
Cross & Cockade International and Wartime magazines. He was
research associate for the Bio-history Cross in the Sky, a book about
Charles 'Moth' Eaton's career, in collaboration with the flier's son,
Dr Charles S. Eaton. He also assisted in picture research for John
Burton's Fortnight of Infamy.
Mitch is now publishing on the WWW various specialist websites combined
with custom website design work.